Question

calculate the number of atoms of o in 88.9 moles of cr₃(po₄)₂.

Explanation:

Step1: Determine the number of O atoms in one formula unit of \(Cr_3(PO_4)_2\)

In \(Cr_3(PO_4)_2\), there are \(4\times2 = 8\) O atoms per formula unit.

Step2: Calculate the number of moles of O atoms

If there are 88.9 moles of \(Cr_3(PO_4)_2\), then the number of moles of O atoms is \(n(O)=88.9\space mol\times8 = 711.2\space mol\)

Step3: Use Avogadro's number \(N_A = 6.022\times 10^{23}\space mol^{-1}\) to find the number of O atoms

The number of O atoms \(N(O)=n(O)\times N_A\)

$$N(O)=711.2\space mol\times6.022\times 10^{23}\space mol^{-1}$$

$$N(O)=711.2\times6.022\times 10^{23}$$

$$N(O)=4.283\times 10^{26}$$

Answer:

\(4.283\times 10^{26}\) O atoms